Dual-tree wavelet based algorithm for speckle reduction and edge enhancement in ultrasound images

Ultrasound images are the important bases of disease diagnostic. Unfortunately, the qualities of ultrasound images are generally limited due to speckle noises. Speckle reduction is an important pre-processing step in the ultrasound image feature extraction, analysis and recognition. In this paper, we present an approach for ultrasound image enhancement. It is designed to utilize the three technologies: the separability and multiresolution properties of the wavelet, the local statistics of each subband and the edge enhancement of the shape. The performance of the proposed method has been compared with that of the commonly novel approaches on both synthetic speckle images and real medical ultrasound images. The proposed method reveals superior performance in term of the PSNR value and perceptible quality. Because of the superior performance in noise reduction and edge preservation, the proposed method is more suitable than the other methods in computer-aided diagnosis.